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Related papers: A Large-Area Search for Low-Mass Objects in Upper …

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We present ALMA Band 7 continuum (340 GHz) and CO J=3-2 observations for an extended sample of disks in the Upper Scorpius OB Association (Upper Sco, age ~ 10 Myr). The targets were selected from previous studies that identified new members…

Solar and Stellar Astrophysics · Physics 2024-10-30 John M. Carpenter , Taran L. Esplin , Kevin L. Luhman , Eric E. Mamajek , Sean M. Andrews

Scorpius-Centaurus is the nearest OB association and its hundreds of members were divided into sub-groups, including Lower Centaurus Crux. Here we study the dynamics of the Lower Centaurus Crux area stellar content. We report the revelation…

Solar and Stellar Astrophysics · Physics 2018-11-28 Bertrand Goldman , Siegfried Roeser , Elena Schilbach , Attila C. Moór , Thomas Henning

We study X-ray emission from young stars by analyzing deep XMM-Newton observations of two regions of the Upper Scorpius association, having an age of 5 Myr. Based on near infrared and optical photometry we identify 22 Upper Scorpius…

Astrophysics · Physics 2009-11-11 C. Argiroffi , F. Favata , E. Flaccomio , A. Maggio , G. Micela , G. Peres , S. Sciortino

We present low-resolution (R=900) optical (576.1--1,051.1 nm) spectroscopic observations of 40 candidate very low-mass members in the Upper Scorpius OB association. These objects were selected using the $I$, $J$ and $K$ photometry available…

Astrophysics · Physics 2009-11-10 Eduardo L. Martin , Xavier Delfosse , Sylvain Guieu

Two eclipsing binaries in the USco association have recently yielded precise values of masses and radii for 4 low-mass members of the association. Standard evolution models would require these dM4.5 - dM5 stars to have ages which are…

Solar and Stellar Astrophysics · Physics 2017-01-11 James MacDonald , D. J. Mullan

I present infrared spectroscopy of 37 brown dwarf candidates in the Upper Sco association, 35 of which are classified as young and cool, making them likely members. This sample includes many of the faintest spectroscopically confirmed…

Solar and Stellar Astrophysics · Physics 2025-05-29 K. L. Luhman

We present results from a large spectroscopic survey of the nearest young association to the Sun, Upper Scorpius, conducted using 2dF/HERMES on the Anglo-Australian Telescope. We use spectroscopic youth criteria such as Li-equivalent widths…

Solar and Stellar Astrophysics · Physics 2025-10-15 Joseph J. Armstrong , Jonathan C. Tan , Nicholas J. Wright , R. D. Jeffries , Janez Kos , E. Fiorellino , Sven Buder , D. Barrios Lopez

We aim at constraining evolutionary models at low mass and young ages by identifying interesting transiting system members of the nearest OB association to the Sun, Upper Scorpius, targeted by the Kepler mission. We produced light curves…

We present the results of a survey for stellar and substellar companions to 82 young stars in the nearby OB association Upper Scorpius. This survey used nonredundant aperture-mask interferometry to achieve typical contrast limits of…

Astrophysics · Physics 2009-11-13 Adam L. Kraus , Michael J. Ireland , Frantz Martinache , James P. Lloyd

We report the discovery of a new low-mass spectroscopic (SB2) stellar binary system in the star-forming region of Upper Scorpius. This object, UScoCTIO5, was discovered by Ardila (2000), who assigned it a spectral class of M4. A KeckI HIRES…

Astrophysics · Physics 2009-11-13 Ansgar Reiners , Gibor Basri , Subhanjoy Mohanty

We have obtained multi-fibre intermediate-resolution optical spectroscopy of 94 photometric and proper motion selected low-mass star and brown dwarf candidates in Upper Sco with AAT/AAOmega. We have estimated the spectral types and measured…

Solar and Stellar Astrophysics · Physics 2015-05-20 N. Lodieu , P. D. Dobbie , N. C. Hambly

We report the detection of seven low mass companions to intermediate-mass stars (SpT B/A/F; $M$$\approx$1.5-4.5 solar masses) in the Scorpius-Centaurus Association using nonredundant aperture masking interferometry. Our newly detected…

We present the results of a near-infrared adaptive optics survey with the aim to detect close companions to Hipparcos members in the three subgroups of the nearby OB association Sco OB2: Upper Scorpius (US), Upper Centaurus Lupus (UCL) and…

We present near-infrared (1.15-2.50 microns) medium-resolution (R = 1700) spectroscopy of a sample of 23 brown dwarf candidates in the young Upper Sco association. We confirm membership of 21 brown dwarfs based on their spectral shape,…

Astrophysics · Physics 2009-11-13 N. Lodieu , N. C. Hambly , R. F. Jameson , S. T. Hodgkin

We have performed a survey for new members of the Ophiuchus cloud complex using high-precision astrometry from the second data release of Gaia, proper motions measured with multi-epoch images from the Spitzer Space Telescope, and…

Solar and Stellar Astrophysics · Physics 2020-06-10 T. L. Esplin , K. L. Luhman

Stellar associations can be discerned as overdensities of sources not only in the physical space but also in the velocity space. The common motion of their members, gradually eroded by the galactic tidal field, is partially reminiscent of…

Astrophysics of Galaxies · Physics 2021-09-01 Vito Squicciarini , Raffaele Gratton , Mariangela Bonavita , Dino Mesa

To address the statistics of binary stars in the 8-Myr old Upper Scorpius star formation region, we conducted speckle-interferometric survey of 614 association members more massive than 0.4 Msun (spectral types earlier than M3V) based on…

Solar and Stellar Astrophysics · Physics 2021-01-11 Andrei Tokovinin , Cesar Briceno

We present mass and radius derivations for a sample of very young, mid- to late M, low-mass stellar and substellar objects in Upper Sco and Taurus. In a previous paper, we determined effective temperatures and surface gravities for these…

Astrophysics · Physics 2009-11-10 Subhanjoy Mohanty , Ray Jayawardhana , Gibor Basri

Free-floating planetary mass objects--worlds that roam interstellar space untethered to a parent star--challenge conventional notions of planetary formation and migration, but also of star and brown dwarf formation. We focus on the…

We present observations of three protoplanetary disks in visible scattered light around M-type stars in the Upper Scorpius OB association using the STIS instrument on the Hubble Space Telescope. The disks around stars 2MASS…

Earth and Planetary Astrophysics · Physics 2021-04-28 Samuel Walker , Maxwell Millar-Blanchaer , Bin Ren , Paul Kalas , John Carpenter